The present invention relates to a relay circuit.
With conventional electromagnetic or solid-state relays, a DC voltage of a given polarity isapplied only once to the relay when operating it. With latching relays, a voltage of opposite polarity is applied to the relay when releasing it. If the relay fails to respond to a rapidly rising edge of the applied voltage for any reason, it is incapable of recovering from the failure and its contacts remain open or closed indefinitely. The same holds true if the relay, once operated, accidentally opens its contacts due to impact from an external source. Such accidental open contacts tend to occur frequently with the latching relays. A prior art attempt to avoid this problem involves the use of a resistor-capacitor circuit which is connected between the relay winding and a DC voltage source through a switch to absorb oscillatory currents generated by the vibratory movements, or "chattering", of the contacts of the switch when it is closed.